Add primitive implementation of GetSaplingAnchorEnd.

src/chain.cpp

@@ -7,6 +7,13 @@
 
 using namespace std;
 
+uint256 CBlockIndex::GetSaplingAnchorEnd() const {
+    // TODO: The block header's hashSaplingAnchorEnd is only guaranteed to
+    // be valid on or after the Sapling activation height.
+
+    return hashSaplingAnchorEnd;
+}
+
 /**
  * CChain implementation
  */

src/chain.h

@@ -321,6 +321,9 @@ public:
     //! Efficiently find an ancestor of this block.
     CBlockIndex* GetAncestor(int height);
     const CBlockIndex* GetAncestor(int height) const;
+
+    //! Get the root of the Sapling merkle tree (at the end of this block)
+    uint256 GetSaplingAnchorEnd() const;
 };
 
 /** Used to marshal pointers into hashes for db storage. */